COLLOIDAL, MACROMOLECULAR AND BIOLOGICAL GELS II

Memo

Many colloidal, surfactant, macromolecular and biological systems such as proteins, hydrophobically modified  polymers, and biopolymers form gels and glasses under different formulation conditions.  Gels can be formed through numerous routes based upon the interactions and self-association present in these systems and can be tuned through modulating the formulation conditions such pH, electrolyte levels, extent of hydrophobic modification, etc. For instance, gels can be obtained through the formation of networks in self-assembling systems such as proteins, surfactant and macromolecular systems, through depletion based attraction in colloid/polymer mixtures, through strong short range attractive interactions present in many colloidal systems etc. Systems having short range attractive and long range repulsive interactions also tend to exhibit rich phase behavior including gel phases. Colloidal glasses are also formed in many cases in which the macroscopic properties such as rheology are influenced by the drastic slowing down of dynamics under high packing conditions. The rich macroscopic properties exhibited by gels and glasses have allowed their wide-scale adoption and exploitation across a multitude of industrial sectors for a wide range of applications. Gels and glasses are utilized in personal care, foods, cosmetics, pharmaceuticals, coatings, separation techniques etc. The development of formulation design rules for these gels to achieve high shelf-life stability and functional performance is driven by establishing the formulation-microstructure-processing-macroscopic property (e.g., rheology) linkages in these systems.  This requires a combination of theory, modelling, novel experimental techniques to develop the required insights and many new developments has taken place over the last several years in these areas.  In addition many new applications are being driven by making the gelation process dependent upon application of various specific stimuli such as light, pH, temperature, etc. in order to generate ‘smart’ responses under different application conditions. This has resulted to developments in the chemistry of various systems and bringing together the knowledge in theory, modelling and experiments of gelling systems. This conference aims to bring together researchers from academia and a wide range of industrial sectors working in the gels area to facilitate cross-disciplinary and cross-industry learnings.